Modelling of switched reluctance machines

Abstract

Analytical models are powerful tools in the preliminary design of electric machines. In this study, a flux-tube model is proposed for switched reluctance machines, in which all the flux paths and the corresponding elements are accurately calculated, iron saturation is intelligently taken into account and formulas are generally developed to attain a continuous model for any range of design parameters. The inductances, flux linkages, torque-angle, maximum torque-current, mean torque-current characteristics are extracted. The special structure of the developed model enables us to extract the air-gap flux density distribution of the machine. Also, finite-element analysis is used in the analyses and evaluation of the model. Finally, the machine has been prototyped by which torque-angle curve and open-loop characteristics are obtained experimentally to evaluate the model. Superiorities of the proposed framework over the previous approaches are demonstrated as well.